Simon sntdbe



SiMo-N SNYDER, or oIN'cINNATLoHIo.

Letters PatentNo. 80,779, dated August 4, 1868. i

`IIlIlItOVl-IIILIEBTT IN TANITING.

dits ttetule narra tu im time tettets ndert animating mi ni tige smite,

To ALL WHoM 1T MAY ooNcERN: e

Be it known that I, SIMON SNYDER, of Cincinnati, in the county of Hamilton, and State of Ohio, have invented a new and improved Method of Tanning, which consists in themodc of constructing and operating a reversible and adjustable tanners vat, wherein the hides or skins are' submerged in ooze,and stratified alter-Y nately with ground tan-bark, or when theooze or tanning-liquor only is employed, interposing between the hide`s, or the folds ofthe hides or skins, to prevent excess of surfaceicontact, matting, or other fabric, of coarse texture, and in subjecting theV entire contents ofthe vat under process to a varying and equable pressure, which facilitates extraction from the tanningmatcrial, and the absorption bythe material being tanned.

To enable others skilled in the art to make and use my invention, I hereby declare the following to be a full and exact description, reference being had to the accompanying drawings, making part of these specifications, and the' letters marked thereon In Figure 2, letter A represents one of my mproved vats, mounted, ready to receive contents, of a. rectangular form, and of dimensions to suit, or, which is preferable, four feet square and eight feet long', made of heavy planks, tongucdand grooved, or grooved for tongue-strips to make joints, with thc ends gained in all around.4

B B B represent clamps, for clamping the vat securely together, composed of bars and rods, or tic-bolts, or wooden clampingbars, with keys or wedges. i

D I) represent trunnions, bolted or otherwise secured on each side of the vat, so that when lodged inthe bearings E E, andthe vat is charged, the centre of gravity in the vat will nearly or quite coincide with its centi of motion, when required to hemoved. i'

F F represent keys, fitting' in dove-tail notches, to lock'the vat in position, at a quarter, half, or whole' turn, which caneasily be arranged tolock the vatalso, at any intermediate part of a turn. A wash-hole is made in the vat, to-vo'idthe liquor, and cleanse the vat, provided with a stop-cock or "plug.

C lrepresents the cover, having a raised surface, to dt closely within top of the vat when-closed. The

'rebated surface fits evenly all round on the top of the vat, with a suitable gasket interposed, before'closing and clamping.

.I do not limit myself to the preciseform otvat, or the parts and material used in its construction, when thel vat will allow the hides or skins to he smoothly stretched or folded, so as to be. stratified with 'bark or matting interposed, and beircvcrsed and adjusted at will by manual power, or at set times by mechanism, to facilitate theiprocess of tanning ,by the friction of percolation, abrasion, and change of pressure, at thesame time exclude free atmospheric contact from th`e contents c if the vat during the action of these forces, in conjunction with t'he well-known chemical forces always developed in the process of tanning.

In order to put my improved vat in operative conditiom'it is mounted in its bearings, and locked iniposi-v tion, with the top uppermost, and thecovcr removed. fOoze. isthen introduced to fill the vat onethird full,

or tlicreabout. Ground tan-barkv is then Spread over the surface of the-ooze, ready to receive the first layer of hides or` skins, stretched smoothly out, or foldedwitli intervening bark or matting. .Then as alternate layers of ground tan-bark and lhides or Skins are successively spread within the Vat, the 'oo'z'e is displaced, until the hides or skins, with the substratum Ofbark, reach the bottom, and the vat is filled to that degree that the cover alone, or with a `follower, will so press upon the contents of the vat, when closed, as to hold the entire stratified contents in the same relative position and arrangement of strata during all 'reversal and adjustment of the var.

If ooze alone is used as the tanning-material, matting, or some fabric of'coarse texture, or'its equivalent, is interposed in lieu of.ba rk, so far as the separatiouof the surfaces ofV the contiguoushides or skins is necessary; in either case, the hides or skins are tobe entirely submerged in ooze. e

When the vat has its'complement of charge, ,the cover is put on, with a gum gasket interposed, to forma joint, onseme other suitable kind of packing,.and is securely clamped together by` means of clamps and tiesome 2 bolts, or wooden clamps and keys. The process is then ready to begin, the contents of the vat being now in the condition known in the art as laid away.

The process of tanning the hides or skins isnow begun, and hastened within the vat by the more frequent reversal and change of position of the vat in the earlier, and gradually less frequent change of position of the vat in the later stages ofthe process. Every change of position of the vat is made to change the pressure within, yet every part of the contents ofthe vat is,-in turn, subjected to the same pressure. Each reversal or change of position of the vat is also made to produce mechanical forces, which eo-operate with the chemical forces and promote a greater' yield of extractive matter fromthe tanning-material', and its absorption and combination with the gelatinous and other portions ofthe material being tanned.

v 'Except at the times of handling or turning, which are much less frequent ih my process than in others heretofore in use, where the contents ofthe vat at all other times of the process lie passive, the air is excluded in order to prevent an injurious amount of galloltannic acid from being formed by the absorption ofthe oxygen ofthe air by the oozc, and too great acidulation therefrom.

Inthe first stages of the process, the vat ought to be reversed or changed at least once in every one-or two hours, then gradually diminish in frequency on to the end of the process. This requirement depends greatly upon the quality of the material being tanned, and the appearances indicated in the progress of th process when the hides/or skins are being handled.

What I claim as my invention, anddesire to secure by Letters Patent,'is-

The method of tanning, substantially as hereinbefore described.

. e SIMON SNYDER. Witnesses:

JAMES Moons, f WILL. TAFT. 

